This invention relates to the art of roll grooving apparatus and, more particularly, to improvements in such apparatus relating to roll and stabilizer guards therefor.
The present invention finds particular utility in connection with portable roll grooving apparatus of the character removably supported on a separate power drive unit which includes spaced apart and parallel support elements for the roll groover and a drive motor having a drive coupling for driving interconnection with a drive shaft of the roll grooving apparatus. While the invention will be illustrated and described herein in connection with such a portable roll groover, it will be understood and appreciated from the disclosure herein that the invention is applicable to other roll grooving apparatus including apparatus integrally mounted on a support and/or drive mechanism.
Generally, roll grooving apparatus includes relatively displaceable first and second support components which respectively rotatably support a driven grooving roll and an idler grooving roll between which a pipe to be grooved is interposed during a roll grooving operation. The grooving rolls are matingly contoured and, in this respect, the driven roll is provided with a peripheral groove and the idler roll is provided with a peripheral projection such that a pipe therebetween is provided with a peripheral groove upon relative rotation of the grooving rolls and relative radial displacement of the grooving rolls toward one another. Displacement of the support components toward and away from one another is achieved in a number of different ways, such as, for example, by a hand or foot operated hydraulic pump, or manually operated force applying arrangements including, for example, force multiplying lever arrangements and screw mechanisms. Further, such roll grooving apparatus often includes a pipe stabilizer arrangement extending laterally outwardly from one side of the apparatus. The stabilizer generally includes a support member slidably supporting a carriage which is displaceable laterally inwardly and outwardly of the apparatus by a crank at the outer end of the support and which includes a rotatable wheel for engaging and stabilizing a pipe being roll grooved.
Many roll grooving machines of the foregoing character include a roll and/or stabilizer guard interposed between an operator of the machine and the grooving rolls and/or stabilizer. Heretofore, such guards have either been stationary with respect to the apparatus or required manual adjustment relative to the apparatus in conjunction with the roll grooving of each different size of pipe within a range of pipe sizes. Such adjustment has, for example, been achieved through the use of bolt, slot and wing nut arrangements. In any event, the inability to adjust the position of a permanently mounted or stationary guard in conjunction with the roll grooving of different sized pipes detracts from the effectiveness of the guard. Additionally, a stationary guard is in the same position for each different size pipe in a range of pipe sizes and, thus, can have optimum effectiveness with respect to just one of the different pipe sizes within the given range. The necessity to manually adjust the position of a guard to accommodate different ranges of pipe sizes is time consuming and thus takes away from production time. In addition to requiring time to make such adjustments, adjustment procedures are sometimes ignored by the machine operator, thus reducing the effectiveness of the guard or guards.
In accordance with the present invention, a guard is provided for roll grooving apparatus which optimizes the effectiveness of the guard for each and every different size of pipe to be roll grooved by the apparatus. More particularly in this respect, a guard in accordance with the invention is mounted on the support member for the idler grooving roll which is displaced relative to the driven roll. Accordingly, the guard is displaceable with the support member, and its position relative to a pipe being roll grooved is automatically and continuously adjusted to optimize its effectiveness. In this respect, for example, if the apparatus includes a stabilizer and a guard associated therewith, the guard engages the stabilizer during a roll grooving operation and is maintained in contact therewith during the roll grooving operation. The position of the guard is adjusted each time the stabilizer is adjusted to accommodate the roll grooving of a different size pipe. If the guard engages a pipe being roll grooved, the position of the guard is likewise automatically adjusted in connection with the size of the pipe. If the apparatus includes a stabilizer, two guards are preferably provided, one for engaging the stabilizer and the other for engaging a pipe being roll grooved. The automatic adjustment of the position of a guard relative to one or the other or both the stabilizer and pipe during a roll grooving operation optimizes the effectiveness of the guard or guards in conjunction with the roll grooving operation.
In accordance with another aspect of the invention, a guard associated with the apparatus for engagement with a pipe being roll grooved preferably interengages with a fixed stop on the support member for the driven grooving roll when the idler roll is displaced away from the driven roll following a roll grooving operation. The stop and guard interengage to displace the guard away from the roll grooved pipe. This facilitates removal of the grooved pipe from between the grooving rolls and also optimizes access to the grooving rolls for changing the roll set.
Preferably, a guard according to the invention is pivotally mounted on the support member for the idler roll and is spring biased to engage one or the other of a stabilizer and a pipe being roll grooved. Accordingly, the position of the guard is self-adjusting, constantly and positively with respect to a pipe being roll grooved and does not require any input from the operator to assure that the guard is properly positioned at all times.
It is accordingly an outstanding object of the present invention to provide an improved guard arrangement for roll grooving apparatus.
Another object is the provision of a guard arrangement for roll grooving apparatus in which the position of one or more guards on the apparatus is self-adjusting relative to the grooving rolls.
A further object is the provision of a guard arrangement of the foregoing character wherein the effectiveness of one or more guards is the same for each pipe in a range of pipe sizes to be roll grooved.
Still another object is the provision of a guard arrangement for roll grooving apparatus in which a guard or guards mounted on a displaceable roll grooving support member for displacement therewith engage one or the other or both of a stabilizer on the apparatus and a pipe being roll grooved during a roll grooving operation to provide a constant effectiveness with respect to the position of the guard or guards independent of the size of the pipe being roll grooved.
Yet a further object is the provision of a guard arrangement of the foregoing character in which a guard interposed between an operator and one of the laterally opposite sides of the grooving rolls is displaceable laterally outwardly of the rolls in response to displacement of the idler roll away from the driven roll to facilitate removal of a pipe from between the rolls following a roll grooving operation and to optimize access to the grooving rolls to facilitate roll changing.